Sir, a recent news item in your columns about human papillomavirus (HPV) (BDJ 2013; 215: 270) entitled HPV linked to a third of throat cancer cases concluded 'These results could have important implications for early diagnosis and risk assessment, as well as the clinical impact of the HPV vaccine, broadening its protective sphere against not only cervical cancer, but oropharyngeal cancers and others, though further research is needed.'

Readers will be interested to learn that there is published a large study conducted on 5,840 sexually active women in Costa Rica (ages 18-25 years) comparing the effects of an HPV vaccine with placebo, in which, after four years, mouthwash samples showed only one woman after vaccine was orally HPV-infected but 15 women after placebo vaccine were infected.1